fix: don't use separate pull requests

Author: gadomski

release-please-config.json

@@ -3,7 +3,6 @@
   "release-type": "rust",
   "bump-minor-pre-major": true,
   "bump-patch-for-minor-pre-major": true,
-  "separate-pull-requests": true,
   "packages": {
     "crates/cli": {},
     "crates/core": {},